Display screen portion with a graphical user interface



The FIGURE is a front view of a display screen portion with a graphical user interface showing our new design.

The evenly spaced broken lines represent the display screen as environment and form no part of the claimed design. The dot-dash-dot broken lines represent the boundaries of the claimed design and form no part thereof. 

CLAIM The ornamental design for a display screen portion with a graphical user interface, as shown and described. 